Control system for feed of articles

ABSTRACT

A control system is provided for discharge of articles in timed relation in a processing system where the articles are fed in single file along a path ending at a discharge station. A pair of holding elements are placed in tandem relation to engage the last and next to last articles before the point of discharge and thereby restrain the flow of the oncoming articles from behind. A control system is provided to initiate and control automatic feeding of the articles.

United States Patent [191 Halv0rsen [11] 3,820,648 June 28, 1974 [54] CONTROL SYSTEM FOR FEED 0F ARTICLES [75] Inventor: Gary A. Halvorsen, San Jose, Calif.

[ 73] Assignees: Genevieve I. Hanscom, Santa Cruz,

Calif; Robert Magnuson; Lois Thomson, Trustees of the Estate of Roy M. Magnuson, part interest to FOREIGN PATENTS OR APPLICATIONS 245,273 1/1926 Great Britain 198/34 Primary Eraminer-Edward A. S roka Attorney, Agent, or Firm-Moore, Zimmerman &

Dubb

[ ABSTRACT A control system is provided for discharge of articles in timed relation in a processing system where the articles are fed in single file along a path ending at a discharge station. A pair of holding elements are placed in tandem relation to engage the last and next to last articles before the point of discharge and thereby restrain the flow of the oncoming articles from behind. A control system is provided to initiate and control automatic feeding of the articles.

5 Claims, 8 Drawing Figures mimmmza m4 SHEET 1 BF 2 III! CONTROL SYSTEM FOR FEED OF ARTICLES DESCRIPTION OF THE INVENTION The present invention relates to the control and feeding of articles in timed relation from a single file, and includes means for insuring that a single article is discharged from the system each time it is called for and that the succeeding articles are fed into position for automatic feeding.

It is a general object of the invention to provide an improved feed control system and method for discharging articles one at a time from a single file of articles.

A further object of the invention is to provide a sys tem of the above character in which the control system will remain idle until the next article is fed into position fordischarge.

Still another object of the invention is to provide a pair of holdingmeans related to a conveyor for articles of flexible character such as bags of articles and to be positioned so as to engage the rear portion of the article in the direction of feed and to position of the front portion in connection with a sensing means.

The above and other objects of the invention are attained as described in connection with a preferred embodiment thereof as illustrated in the accompanying drawings, in which:

FIG. lis a fragmentary plan view of apparatus embodying the control system of the instant invention;

FIG. 2 is an end elevational view of the control system taken in a plane indicated by the line 2--2 in FIG. 1;

FIG. 3 is a sectional view through the apparatus taken as indicated by the line 3-3 in FIG. 1;

FIG. 4 is an elevational view of the two adjacent holding means from inside of the track, the view being indicated by the line 44 in FIG. 2;

FIGS. 5, 6 and 7 are schematic views illustrating the operation of the pair of holding means in effecting release of a single article on command;

FIG. 8 is a schematic wiring diagram of certain of the control functionsand elements of the invention;

Referring to FIGS. 1 through 4, the invention includes a conventional shuffle feed mechanism 10 leading to a point of selective discharge to either one of two conveyors by means of a discharge gate 11 suitably mounted for pivoting movement on the frame so that it is either underneath the endmost discharge point 12 of the shuffle feed mechanism 10 or is absent from this point to control the discharge of articles selectively onto a first feeddramp 13 or a second feed ramp 14. The feed ramp 13 leads to a feed path 17 defined by two sideguides 16 suitably mounted on the frame 18. Similarly the ramp 14 leads to similar guides 16a and a path 173: and both of these paths defined by the guides 16 and 16a are on a belt conveyor 21 which is suitably mounted on driving and driven drums and moves in the direction indicated by the arrows in FIG. 1.

Associated with the shuffle feed mechanism, its motor and the conveyor 21 is a pair of photoelectric units 15, one for each of the paths l7 and 17a, which operate in a conventional manner to sense the presence or absence of bags on the conveyor in each path and to control the operation of the conveyor, the shuffle feed mechanism and the discharge control gate 11.

i In operation, flexible plastic bags of cigarette papers, for example, are fed by the shuffle feed conveyor 10 and discharged one row at a time into the discharge area where the control gate 11 is provided and this con trol can be operated so that either alternate rows are discharged onto the ramps 13 and 14 or so that all the rows are discharged onto one of the ramps as required by production.

The operation of the feed gate 11 is provided by an air cylinder 26 mounted on a bracket 25 and controlled in a suitable manner as may be desired.

At the discharge end of the apparatus, a pair of discharge elements of the vacuum type are provided including swinging arm 36 (FIG. 1) at each one of the discharge stations which are adapted to pick up a bag 37 and swing it in the direction of one or the other of the arrows .in the case of the lower of the two positions shown in FIG. 1, to the dotted line position 36a where the vacuum is released and the bag is discharged in timed relation to a suitable point of delivery.

Ahead of these pick-up points of the bags 37 a pair of deflectors or bag turners 38 are provided at each of the discharge to insure the bag going into position beneath the vacuum pick-up on the arm 36. This construction is conventional.

The discharge control means from each of the indi vidual paths of single file bags comprises a pair of holding means or plates 41 and 42 (FIGS. 1, 4 and 5). Each of these holding means or plates is carried on the end of aspring-urged piston rod 43 of an air cylinder 44 or 45 and the operation of these air cylinders is controlled by respective solenoid control valves 47 and 48 (FIG. 1). i

In FIG. 7 the control apparatus is shown in its normal position with both holding elements or plates 41 and 42 extended and engaged under air pressure with respective bags 37a and 37b, while bag 370 is in trailing position and subject to the drive of the belt 21.

At a given signal from the apparatus, the holding means 41 (FIG. 5) has its valve 47 operated so that the holding means on plate 41 is moved by spring pressure to'the position shown in FIG. 5 where the bag 37a is shown released for travel with the conveyor 21 in the direction of the arrow. While the bag 37a still stands in the path of the light ray between the retro-reflective mirror 51 and'the photoelectric control unit of the retro-reflective system 52, the control elements stay in the position shown in FIG. 5 having been trippedto this position for example by cyclically operable cam whose specific nature forms no part of this invention.

When the bag 37a has traveled beyond the retroreflector 51 (FIG. 6) the retro-reflective element 52 is activated and disables the holding element 42 as shown in FIG. 6. When the bag 37b travels from position shown in FIG. 6 to the position of the bag 37a shown in FIG. 7, two control functions are exercised. The holding element 41 is projected after the light beam has been broken by the front portion. of this bag and engages the rear portion of this bag. Thereafter, the holding element 42 similarly engages a new second bag 37b as all the bags in this line move up one position.

This operation is repeated during cycling of the apparatus.

In order to control the above functioning of the parts, a circuit of the type shown in FIG. 8 is desirable and this includes a relay 61 having one set of contacts 62 normally closed by a contact strip 63, and a set of normally open contacts 64 controlled by a contact strip 65 and forming a switch 64, 65. In circuit with the coil of the relay 61 and with the switch 64, 65 is a pair of normally open contacts 71 controlled for closing by a contact strip 72 forming a switch 71, 72 operated by a suitable cam 73. The circuit also includes a solenoid 47a associated with the solenoid control valve 47 and a second solenoid 48a of the control valve 48. The source 110 volts A.C. is indicated at 76 and one leg of this includes an on-of switch 77 controlled manually.

It will be seen from this wiring diagram that when both the switch 71, 72 and the switch 77 are closed, the relay 61 will be energized so that the circuit controlled by the switch 62, 63 to the solenoid 47a will be opened thereby moving the holding means 41 to inactive position to release the endmost bag 37a as seen in FIG. 5.

When the light ray from the retro-reflector 51 operates the retro-reflector control element 52 the contact 77 is opened andthe solenoid 48 is operated to move the second of the holding elements 42 to inactive position as shown in FIG. 6.

When the oncoming bag again is engaged by the holding element 41 and interrupts the control for the retro-reflector control element 52 the second bag is also engaged by the second holding element 42 and the parts restored to the position shown in FIG. 7.

While I have shown and described a preferred form of the invention, it will be apparent that the invention is capable of variation and modification from the form shown so that the scope thereof should be limited only by the proper scope of the claims appended hereto.

I claim:

1. In a feed control system for articles such as bags of products, a conveyor for conveying articles to a dis charge point, a pair of holding means arranged in tandem adjacent the discharge point for engaging and holding the endmost and next-to-endmost articles,

means for sensing the presence or absence of an endmost article at a discharge station, control means under control of said sensing means for disabling said first named holding means and effecting discharge of the endmost article, means activated in response to absence of an article from the endmost discharge station and operating to disable said second holding means for the next-to-endmost article, whereby next-to-endmost article is released for travel with said conveyor from said second holding station to the first station, and means responsive to the sensing means for the last station for re-engaging said first holding means with said article whose presence is being sensed.

2. In a feed control system as recited in claim 1, including a cyclically operable means for controlling the release of an article from the endmost holding station.

3. In a feed control system as recited in claim 1, in which the sensing means is a retro-reflective sensor.

4. In a feed control system as recited in claim 1, in which said holding means comprises a fluid operated plunger.

5. In a feed control system as recited in claim 4, in which said holding means also includes a plate having a beveled end facing in the direction of flow of the articles on said conveyor. 

1. In a feed control system for articles such as bags of products, a conveyor for conveying articles to a discharge point, a pair of holding means arranged in tandem adjacent the discharge point for engaging and holding the endmost and next-to-endmost articles, means for sensing the presence or absence of an endmost article at a discharge station, control means under control of said sensing means for disabling said first named holding means and effecting discharge of the endmost article, means activated in response to absence of an article from the endmost discharge station and operating to disable said second holding means for the next-to-endmost article, whereby next-to-endmost article is released for travel with said conveyor from said second holding station to the first station, and means responsive to the sensing means for the last station for re-engaging said first holding means with said article whose presence is being sensed.
 2. In a feed control system as recited in claim 1, including a cyclically operable means for controlling the release of an article from the endmost holding station.
 3. In a feed control system as recited in claim 1, in which the sensing means is a retro-reflective sensor.
 4. In a feed control system as recited in claim 1, in which said holding means comprises a fluid operated plunger.
 5. In a feed control system as recited in claim 4, in which said holding means also includes a plate having a beveled end facing in the direction of flow of the articles on said conveyor. 